Saturday, 7 April 2018

Regent Honeyeater in the spotlight



Regent Honeyeater - Capertee 
A dazzling combination of vibrant colours explodes from a cluster of pink mugga ironbark flowers. A Regent Honeyeater attacks the flowers with gusto before another honeyeater, then another appears. An estimated 10–12 honeyeaters are present, flitting between ironbarks and yellow box trees on a grassy woodland slope in Capertee National Park, on the western fringe of the Blue Mountains World Heritage Area in NSW.
Regent Honeyeater adult & juvenile - Capertee
I had seen the critically endangered Regent Honeyeater just three times over close to 50 years of birding - once at Storm King Dam near the NSW-Queensland border; once at Stanmore in south-east Queensland; and once at Glenbrook, west of Sydney. To see them again at Capertee was a joy. What was particularly encouraging was that two recently fledged juveniles were among the group, so they had nested successfully in the area. In another part of the Capertee Valley the next day, I found a second group of 3-4 birds, so my life tally of encounters with this species almost doubled in two days.
Extensive clearing of its woodland habitat in south-east Australia for agriculture, combined with an explosion in populations of the aggressive Noisy Miner, has pushed this beautiful bird to the brink, with its population estimated as low as 400-500, down from about 1,500 in the 1990s. BirdLife Australia, in co-operation with other groups, is engaged in a well-targeted and energetic program to rehabilitate the habitat of the Regent Honeyeater and other declining woodland birds, while a captive breeding program is trying to boost honeyeater numbers.
Box-ironbark woodland - Gwydir River, NSW
Hundreds of people are lending a hand with tree-planting in NSW and Victoria as part of the Regent Honeyeater Project. It's one of Australia's biggest volunteer-based conservation programs, with more than 1,800 hectares of core honeyeater habitat being targeted for revegetation in north-east Victoria, Captertee Valley and the Gwydir River area, west of Armidale in NSW.
Now, it is possible the tide is turning. An annual survey organised in NSW last August by BirdLife Australia – not long before I saw the birds in Capertee - resulted in 53 sightings. This was significantly higher than surveys over the preceding five years, when an average of 10-15 birds were counted annually. Fair-sized flocks of Regent Honeyeaters were seen regularly in the Capertee and Lower Hunter valleys of NSW in particular.
Revegatation project - Gwydir River, NSW
In the Chiltern-Mt Pilot National Park of Victoria, a former stronghold for the species, increasing numbers of captive bred birds appear to be surviving in the wild; 101 captive bred birds were released there in 2017, the largest of five such releases. Two birds found in March this year in Gippsland had travelled 200 kilometres since their release at Chiltern in 2017. This follows another bird released in 2015 which crossed the Great Dividing Range to South Gippsland in 2016, before returning to attempt to nest at Chiltern in 2017 – a round trip of 540 kilometres, the longest recorded movement of the species.
Captive breeding programs for endangered species do not always work, and may perversely have adverse consequences. But the Taronga Zoo-based Regent Honeyeater program could be on track following earlier challenges, when released birds evidently failed to survive.
Captive bred birds struggle to nest successfully; during the 2015 season at Chiltern, 64 per cent of nesting attempts failed to reach the egg stage. However, more than 70 per cent of released birds were alive 10 weeks after release, which BirdLife Australia's Regent Honeyeater recovery co-ordinator, Dean Ingwersen, describes as an “excellent figure by translocation/release standards”. Dean adds that the rate at which released captive birds are being seen 12 months post-release almost matches the rate of resightings of banded wild birds: “We think this is demonstrating good long-term survival of released birds.”
Regent Honeyeater, Capertee
Congregating in flocks was a hallmark of the species; the birds I saw at Storm King Dam, back in 1973, were in a flock of 15. Increasingly, however, records of the species over the ensuing decades were of single birds, pairs, or at best, small flocks. This reduction in flocking may reduce the ability of the species to defend itself again hordes of Noisy Miners, which are intolerant of other species. Field researchers have established that controlling Noisy Miner numbers in the box-ironbark woodlands favoured by Regent Honeyeaters boosts the chances of the latter nesting successfully. The flocks just might be making a comeback, with as many as 20 birds seen together in the Lower Hunter.
It is too early, however, to be popping the champaign corks. Recent increases in sightings may be due to unusually good flowering events, and the long-term picture remains uncertain at best. Populations of other woodland birds such as Grey-crowned Babbler, Hooded Robin and Black-chinned Honeyeater continue to decline. Conversely, numbers of Noisy Miners appear to be ever rising, and keeping them in check in the favoured haunts of the Regent Honeyeater is a huge logistical challenge. With the species estimated to have lost greater than 85 per cent of its habitat to the bulldozer, extensive areas of woodland continues to be cleared at unacceptable rates in Queensland and in NSW.
A sign in Capertee Valley
Dean Ingwersen points to new challenges, including the recently discovered problem of nests being predated by sugar gliders and squirrel gliders. Various research programs underway - in conjunction with captive breeding, habitat rehabilitation and other measures - hold the key to future solutions. Funding has been secured to attach satellite transmitters to five wild birds to track their movements. This is aimed at determining where the birds go to over summer, when records of Regent Honeyeater are scant. Funding has also been secured for trial interventions at nests to improve breeding success, with nest failure identified as a major impediment to the recovery of the species.
Says Dean: “The recovery team has worked tirelessly over the past couple of years to produce a robust and holistic recovery plan, and we are incorporating new research findings going forward as they arise... The whole recovery program is still a work in progress, and not surprisingly we’ve had some failures so far, but we’re trying hard to make our work as adaptive as possible.”

Regent Honeyeater - Capertee



















1 comment:

  1. I have seen the species at the Warrumbungles, Canberra and Congo (South Coast NSW, not Africa).

    You mention the threat from Noisy Miners. My understanding is that Miners do not favour areas with well developed scrub understorey. Is there a link between the increase of this species and the increase in Habitat Reduction Burns in National Parks?

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